As Dubai’s building boom continues at a breathtaking pace, German concrete specialist Putzmeister – through its local partners in the region – is trying to live up to the challenges through the delivery of products and solutions that best suit these multi-million-dollar projects.
Over the years, Putzmeister (PM) pumps have been used on the biggest, tallest and ambitious developments in the region and several Putzmeister customers in the UAE – such as Unimix, German Gulf Enterprises (GGE), and Ready Mix Beton (RMB) – have been operating their fleet of pumps and supplying concrete on these projects.
Unimix
One of Putzmeister’s major clients in Dubai, Unmix has not only supplied quality concrete but also provided pumping service to an impressive list of high-rise buildings that include the seven-star Burj Al Arab hotel, the 309-m and 355-m high hotel and office towers of Emirates Towers, the 51-storey Marina Crown Tower luxury apartment complex and several other major projects including the most recent ones such as the Palms at Jumeirah and Jebel Ali, and the Burj Dubai, the world’s tallest tower.
Both the Palm Jumeirah and Palm Jebel Ali have luxury property sprouting up all over the man-made islands and once complete, each of the two island groups will offer dozens of five-star hotels, 2,500 exclusive beach villas, 2,400 apartments with a sea view, marinas, restaurants, leisure parks, shopping centres and much more. Work on the Palm Jumeira is expected to be completed by the end of 2007. The villas are expected to be ready by the end of 2005, the trunk apartments in the second quarter of 2006, and the Crescent projects by the end of 2007.
Skilled concrete technologists at Unimix develop various mixture breakdowns: concrete with 100 N/sq mm compressive strength, self-compressed concrete with low heat of hydration and also concrete types of high strength with equally high elasticity. The various concrete mixtures mentioned above will be developed by Unimix and pumped with Putzmeister high-performance pumps for the prestigious Burj Dubai.
In detailed tests, Putzmeister testing engineers are said to have checked the pumpability of this extremely superior concrete and simulated the high pressures expected. Although figures regarding the final pumping height have remained a secret, Unimix is said to have decided on the members of the 7 to 10-member-strong concrete team, who have been drawn from the company’s best and most experienced people.
In the last four years, Unimix has doubled its capacity and has invested not only in modern concrete mixing plants and truck mixers, but also in concrete pumps and booms, says a Putzmeister spokesman. “Following an active investment policy to meet the growing requirements of the market, the company currently operates 120 truck mixers, 20 truck-mounted concrete pumps, 16 stationary concrete pumps and 36 stationary booms. The Unimix mixing plants produced approximately 1.5 million cu m of concrete in 2004, and around 75 per cent of this was pumped.”
German Gulf
German Gulf Enterprises which has been a reliable partner of Putzmeister in the region for over 30 years has been offering valuable advice to customers and contractors on how to maximise performance using Putzmeister’s range of pumping equipment. On the recommendation of GGE, almost all operators of Putzmeister concrete pumps in the UAE have their machines delivered equipped with the “16 H” pump assembly, which are designed to handle delivery pressures of up to 85 bar or rates of up to 160 cu m/h (maximum/theoretical) when pumping concrete through the boom pipe. The assembly can achieve concrete pressures of up to 130 bar (maximum/theoretical) in stationary operation, when the hydraulic cylinders are acted on from the piston side.
Simply, PM concrete pumps with the “16 H” assembly therefore have greater performance in reserve for demanding situations (as in low cement content, unfavourable concrete grading curve, low w/c (weight of water/weight of cement) value). The advice of GGE has also served to win favour for specific variants from the PM standardised modular system in the areas of S transfer tubes, hoppers, plunger cylinders and water tanks.
Ready Mix Beton
One of the largest concrete manufacturers and pump service companies in the UAE, Ready Mix Beton boasts of 34 mixing pumps, numerous stationary booms and approximately 40 concrete pumps.
One of mobile RMB’s mixing plants is currently operating on the huge construction site of the Jumeirah Beach Residences.
The plant, which runs 24 hours a day and produces 100,000 cu m of concrete every month, was originally only intended to produce concrete for a few months. However, the huge demand for concrete for the Jumeirah Beach Residences (JBR) project – a total of 22 of the 40 JBR high-rise apartments were supplied by RMB, as well as several construction sites on Palm Island – has considerably increased the originally planned number of operating hours, says a spokesman.
The RMB mixing plant on the Jumeirah Beach Residences site includes a fleet of 35 truck mixers and seven concrete pumps, including three stationary high-pressure pumps BSA 2110 HP-D and BSA 2109 H-D. The Putzmeister pumps play an important role in supplying concrete for the stationary booms to the upper levels. Concrete in pressure strength class C60/75 is handled here and pumped up to the height of 55 floors.
To deliver quality readymix in the exceptionally high temperatures of the region, RMB has been adding concrete additives, such as set retarding admixtures and deflocculants to the mix.
Over the expansive construction site, RMB employees convert the high-pressure concrete pumps as required and connect the machines to the various risers for the individual high-rise towers. In 2004 alone, RMB commissioned 14 new Putzmeister MX 28 and MX 32 stationary booms for this project.
During the summer months in particular, employees on the construction sites make sure that the temperature of the concrete during delivery and the heat of hydration after placement in the formwork are kept under controlled conditions and under cover. Before filling the truck mixer, flakes of ice (100 to 120 kg/cu m) are often added to the concrete batches. The concrete can therefore be kept “cool” at around 25 deg C to 30 deg C until arrival at the construction site.
